/*
 * CTerrainRect.h, part of VCMI engine
 *
 * Authors: listed in file AUTHORS in main folder
 *
 * License: GNU General Public License v2.0 or later
 * Full text of license available in license.txt file, in main folder
 *
 */
#pragma once

#include "../gui/CIntObject.h"
#include "../../lib/int3.h"

VCMI_LIB_NAMESPACE_BEGIN
struct CGPath;
VCMI_LIB_NAMESPACE_END

enum class EMapAnimRedrawStatus;
class CFadeAnimation;

/// Holds information about which tiles of the terrain are shown/not shown at the screen
class CTerrainRect : public CIntObject
{
	SDL_Surface * fadeSurface;
	EMapAnimRedrawStatus lastRedrawStatus;
	std::shared_ptr<CFadeAnimation> fadeAnim;

	int3 swipeInitialMapPos;
	Point swipeInitialRealPos;
	bool isSwiping;
	static constexpr float SwipeTouchSlop = 16.0f;

	void handleHover(const Point & cursorPosition);
	void handleSwipeMove(const Point & cursorPosition);
	/// handles start/finish of swipe (press/release of corresponding button); returns true if state change was handled
	bool handleSwipeStateChange(bool btnPressed);
	int3 curHoveredTile;

	int3 whichTileIsIt(const int x, const int y); //x,y are cursor position
	int3 whichTileIsIt(); //uses current cursor pos
	void showPath(const Rect &extRect, SDL_Surface * to);

	bool needsAnimUpdate();
public:
	int tilesw, tilesh; //width and height of terrain to blit in tiles
	int moveX, moveY; //shift between actual position of screen and the one we wil blit; ranges from -31 to 31 (in pixels)
	CGPath * currentPath;

	CTerrainRect();
	~CTerrainRect();

	// CIntObject interface implementation
	void deactivate() override;
	void clickLeft(tribool down, bool previousState) override;
	void clickRight(tribool down, bool previousState) override;
	void clickMiddle(tribool down, bool previousState) override;
	void hover(bool on) override;
	void mouseMoved (const Point & cursorPosition) override;
	void show(SDL_Surface * to) override;
	void showAll(SDL_Surface * to) override;

	void showAnim(SDL_Surface * to);

	/// @returns number of visible tiles on screen respecting current map scaling
	Rect visibleTilesArea();

	/// animates view by caching current surface and crossfading it with normal screen
	void fadeFromCurrentView();
};